A television station that can be watched by 7 million people has a much greater outreach than a meeting at the city hall with 25,000 people.
Explanation:
It seems quite obvious that a lot of people own a television. By telecasting programs on a television media, outlets can increase their outreach to a much larger audience.
While a meeting in a city hall filled with 25,000 people can only prove to reach out to the people who are present there, a television program can reach out to people who are not only in that city but who are in other parts of the world too, thus making outreach as the suitable word.